Doctoral student tackles barley yellow dwarf virus threatening wheat crops
Shirin Parizad is developing effective strategies to help manage the most significant disease of small grains globally.
With expertise in plant pathology, entomology, and molecular biology, Shirin Parizad is well-equipped to address the challenges posed by vector-borne plant viruses in agricultural fields.
While obtaining her Ph.D. in plant pathology from the University of Tehran, she realized that understanding insect vectors – or how insects transmit disease – is critical for minimizing the transmission of plant viruses in crops. After deciding to pursue a second Ph.D. in entomology, Parizad joined Virginia Tech in the spring of 2023 to work with Arash Rashed, professor of entomology and director of the Southern Piedmont Agricultural Research and Extension Center.
“Virginia Tech has been the ideal place for my research due to its excellent faculty members in the entomology department and its strong emphasis on integrated pest management programs that encompass both plant disease and pest control,” said Parizad.
Her research focuses on filling critical knowledge gaps in the epidemiology of barley yellow dwarf virus, which is the most significant viral disease of small grains globally and affects crop yield and quality. It has been a reoccurring condition in Virginia wheat in recent years.
Working in the Southern Piedmont Entomology Laboratory, Parizad examines the roles of invasive aphids and alternative host plants in barley yellow dwarf virus transmission to understand better how environmental changes affect its spread. This knowledge is critical for developing effective management strategies for the virus in small grain production systems.
She is investigating the impact of two key factors: the invasive aphid species Metopolophium festucae cerealium and alternative host plants such as tall fescue on the transmission of barley yellow dwarf virus.
First identified in U.S. wheat crops in 2011, the Metopolophium festucae cerealium aphid species causes significant direct feeding damage to crop, but ts effectiveness as a virus vector remains unclear. Parizad aims to investigate the genetic variation within Metopolophium festucae cerealium populations and whether it is influenced by geographic location and/or host plant species.
In connection with this research, she was recently awarded grant funding by the Invasive Species Collaborative at Virginia Tech.
Additionally, Parizad examines how changes in grazing land management may influence aphid dynamics and the spread of barley yellow dwarf virus into field crops. Given that grazing lands often border croplands, understanding these interactions is essential for predicting disease risk in nearby wheat fields.
“Shirin’s work identifying alternative barley yellow dwarf virus and aphid host plants and habitats is highly relevant to Virginia's integrated livestock and crop production system where forage crops may also function as reservoirs for crop pests and pathogens,” said Rashed.
In addition to her current research, Parizad has worked with industry collaborators to develop grant proposals to promote and evaluate various pest management practices to control barley yellow dwarf virus. Notable projects include securing funding for integrated pest management for cereal aphid and barley yellow dwarf virus control from the U.S. Department of Agriculture's National Institute of Food and Agriculture and exploring the benefits of insecticide seed treatments in wheat through the Virginia Agriculture Council.
“I aim to conduct applied research that directly benefits farmers and contributes to environmental health,” said Parizad.
She expects to complete her Ph.D. in entomology by 2026, with future work focused on developing sustainable strategies to manage viral diseases and insect vectors.
